What’s the Pros and Cons of Lithium Titanate Batteries used in Electric Vehicles

Author:Source:Datetime: 2016-10-07 10:41:08

Lithium titanate is a useful material, but the advantages and disadvantages are more obvious. Low energy density is its most prominent problem, so it is more suitable for some special purpose electric vehicles, if want the car run away far, please ignore it.

Lithium battery, must have positive and negative materials, that is not clear what is, its difficult to talk about whether good for using. Lithium titanate is also no positive or negative, but it does not matter, here we will simply analyze.

First, paste the literature on lithium titanate introduction:

175mAh / g theoretical capacity, the lithium potential of 1.5V - and therefore does not produce SEI, irreversible capacity is low (so the material life and safety), embedded lithium when the volume strain is less than 0.2%, so Material structure is particularly stable. When made Li4Ti5O12, charge is full of Li4Ti5O12. The material is safe, long life, excellent performance in power and low temperature applications.

The following analysis:

Capacity is not low, 175mAh / g, but this is only capacity, not energy, voltage multiplied by the power is the energy. This material voltage is 1.5V, OK.

The problem comes, this material can do both positive and negative, you can do. If you do the cathode, then it is necessary and basic graphite anode, the battery is 1.5V battery (generally lithium batteries, 3.4,3.7V have, and now there are 4V).

If it is to do the cathode, the first charge to be embedded lithium, which requires the cathode must contain lithium. General use of the anode, such as graphite, are not lithium, which requires lithiation. Lithium-based graphite / silicon negative technology seems to have this, but I listen to the Japanese experts here we have talked about speaking, I feel like what is more mature technology, at least personally think that lithium is far more practical than lithium titanate .

If you do negative, OK, this is it the Bank. It is a little higher voltage, but just with the electrolyte stable coexistence, will not generate SEI film. So material safety is good, material charge and discharge strain is small, known as the "zero strain material", short life, large charge-discharge is also more tolerant, I heard that there are 10,000 life.

Positive and negative battery match is more important content: such as the negative special cattle, ten thousand times the life, but unfortunately the positive can only hold 500, the same game. Several typical cathode materials, such as ternary (now also good), lithium cobalt oxide, lifepo4, lithium manganese oxide, lifepo4 battery packis still the highest life expectancy, lithium iron phosphate power performance is also very good, so personally think and lithium titanate with more reliable. However, this battery, the voltage is only 3.4-1.5 = 1.9V, the basic or a miserable (ordinary lithium iron phosphate battery to graphite as the anode, 3.3V or so voltage). The energy density is correspondingly very shabby.

In short, the lithium titanate this material, or voltage and then low (as negative), or voltage and then a little higher (as positive), the situation may be much better.

In addition, the price of your material is certain (RMB / kg), after all, titanium is not something particularly cheap, you can cheap ferromanganese cheap? Coupled with the low energy density (WH / kg), so the unit energy (RMB / WH) price, will only be more uncompetitive. (Your electric vehicles every day too expensive) to say to say, in fact, people also have advantages, material stability, security, large power performance good, so for the "fast charge" "power" use, it is more appropriate, it is not Problem, people did not lie.

However, this power-based use is by sacrificing energy density, previously loaded 100kg battery, and now if you want to run so far, it is necessary to install 200kg ... ... so the corresponding also made some adjustments, such as less installed battery , And then run a trip charge once, every time fast charge. In fact, I think, this can be considered a successful mode of operation. But really have the unit of energy (RMB / WH) the price of this account clear, after all, recognized products, the cost must be a bit competitive, and at this point seems to be less optimistic about lithium titanate.

PS: Lithium titanate cathode cooperate with lifepo4, give full play to stability, long life, high power advantages, do some power type, energy storage battery, or more reliable. Such as use it in portable solar power generator.